Block system



y 4, 1939- M. H. LOUGHRIDGE I 2,164,331

BLOCK SYSTEM Filed Feb. 24, 1956 2 Sheets-Sheet 1 /6 39 x15 34 [Q1132 4 37 -56 1m ff [6 n W V 16 Y L v E M c 4 7! 7 33:- 40 4/4 38 a 40 (a 7 I B v r 14 0 25 s j;

Bil-J! -wr 64 15 A9 July 4, 1939- m. H. L'QUGHRIDGE 2,154,331

BLOCK SYSTEM Filed Feb. 24, 1936 2 Sheets-Sheet 2 l% INVENTOR.

Patented July 4, 1939 UNITED STATES PATEN OFFICE Matthew H. Loughridge, Bogota, N. J. Application February 24, 1936, Serial No. 65,249

16 Claims.

This invention relates to block systems, such as are used for automatically spacing trains on a railway track, and train control is included as a feature of the system. The system is shown applied to a railroad in which the track rails are divided into track circuits in a well known manner for defining the limits of the blocks.

An object of the invention is to provide ablock system which eliminates relays and apparatus having moving parts on the trackway. while providing a two and three block control for selectively operating translating devices on the train or on the track in accordance with traflic conditions. Another object of the invention is to shunt an A. C. track circuit by shunting the primary of the track transformer. Other objects of the invention will be more particularly understood from the detailed description in the following specification and the accompanying drawings, selected to show several applications of the invention, and in which:

Fig. 1 is a wiring diagram of one application of the system to a railroad using track circuits, trackway signals and train control;

Fig. 2 is a modifiedform of the invention applied to railroads using track circuits, with train control;

Fig. 3 is a circuit showing an alternative arrangement to Fig. 2 with the object of maintaining the closed circuit principle; Fig. 3a shows the system applied to three block control.

In this invention an alternating current transmission line is used to operate the block system which is preferably charged with current at a comparatively high frequency. Through a transformer and a rectifier this line feeds the track circuit. The rectifier is inductively coupled in the circuit in one application and has the effect of doubling the frequency. The primary circuit of the transformer connects through a condenser of suitable'capacity with the track circuit of the block ahead which has the effect, when a train is in the block, of effectively deenergizing or'suppressing the circuit of the block in the rear.

The transformer connection to the track circuit which is used to suppress the current to the rectifier is additional to the regular circuit energizing the track circuit and a condenser is provided in this connection of such capacity that while the energy to the rectifier is suppressed the higher frequency current of the track circuit is not materially affected thereby thus providing a system which selectively deenergizes the rear track circuit by a train in the block.

by a train shunting the track rails, but

In Fig. 1, the running rails are indicated by H and I2 and are divided by the insulated joints [3 into the block sections a, b, and c. The track circuit is fed by wires 14 through condenser l5 and transformer l6. Wayside signals may be used if desired as indicated at 24 and 21. These signals are operated by the track connection l1, through condenser 18 and transformer I!) to the track. relay 20, which is energized in response to the energy from transformer 16 when the block is clear. The signal 24 for block a indicates that the block is unoccupied and is energized from the battery wire B through contact 2| of relay 20, wire 23 to the signal mechanism, and return to the battery by wire 0. The signal 27 is in the stop position because b is occupied by a train and relay is deenergized.

This signal is controlled similarly to signal 24, and in addition, has a caution control starting from battery wire B through contact 22 of relay 20 20 for block a, wire 25, contact 22 of relay 20 for block b, and wire 26 to the signal mechanism. The arrangement in Fig. 1 may be used with the continuous type of train control which makes wayside signals of minor importance.

, The transmission line 3|, through transformer 32, feedstransformer 34, connected across the wires 33, and the secondary of transformer 34, through wires 35 and 36, connects to the full wave rectifier 31, and fromthis rectifier by wires 38 and 39to the transformer I6 which is used to feed the trackcircuit.

It will. be noted that the primary of transformer 34 is connected in multiple circuit with the track rails II and I2 by wires 33 through the condenser 40 of such capacity that a train in the block practically short circuits the primary of transformer 34 and the energy which is fed to the rectifier 31 which, in turn, practically deenergizes the track circuit fed through the recti- 40 fier. The condenser 40 and the frequency of the current in the circuit in wires 33 selectively isolate this circuit of wire l4 and the circuit of transformer I9 energizing relay 20. It should be understood that the current in the circuit on wires 33v and the curent in the circuit on wires 11 are detuned with respect to each other by condensers 40 and I8 so that 34 is deenergized this circuit, when the block is clear, has no material effect in energizing relay 20.

A typical train control system is indicated by the coils 63 and 64 mounted on an inductor and carried over the track rails to be influenced by the current from transformer l6. These coils s5 are connected through the circuit indicated by 65 and the condenser 66 with the amplifier A, and from the amplifier by wires 61 to the transformer H, and from this transformer through the condenser 12 to the train control relay 68. This relay controls the translating device 89 from the battery wire B through contact 10 to the device 69 and return to battery on wire 0. The train control system described is .typical of the continuous type well known in the art, and is tuned to respond to the current from transformer l6 by condensers l5 and 66. Thus a train in the block ahead will deenergize relay 88',- but if the block ahead is clear, the current from transformer [6 will maintain relay 68 energized. The current in the control circuit for relay 68 is tuned not to respond to the current from wires 33.

It should be noted that the primary of transformer 34, which controls the current for feeding .the track circuit is shunted on wires 33 by a train on the track. This is a more effective shunt for deenergizing the track circuit than the shunt of the secondary of transformer 16 on wires Hi. This is due to the fact that the resistance of the shunt is the same in both cases but the voltage of the primary of transformer 34 is usually higher than the voltage of .the feed t wires. I4.

In the diagram in Fig. 2, transformer core 42 has a primary coil 4i and two secondaries 43 and 44. Secondary 43 energizes coil 46 of the transformer 41 through a rectifier 45, and the-coil 44 energizes coil 49 of transformer 41 through the rectifier 48. The secondary coil 50 of transformer 41 by the wires 5| feeds the track circuit. The rectifier 45 stops one-half of the A. 'C. current in coil 43, and rectifier 48 stops one-half of the A. C. current in coil 44, one rectifier being the complement of the other so that when they are connected as shown the secondary coil 50 is energized with the full wave current. The :coil 44 is bridged across the track rails by wires 52, through the condenser 53 and the reactance 54 with the result that when a train occupies a track circuit the coil 44 and coil 49 are substantially short circuited through condenser 53 and the secondary coil 50 of transformer 41 is fed only from coil 46 which has a half wave characteristic, and this characteristic is transmitted to the track circuit as long as the block is occupied. The vehicle apparatus is provided with inductors 8| and 62 coming under the influence of the current in the running rail, and through the amplifier energizes the relay 68 and the brake controlling device 69. The relay 68 controls the propulsion motor ll through contact 10 so that the system controls the propulsion and braking of the vehicle. Reactance 13 is bridged across the device 69 to regulate its operation.

A train in block a. reduces the current energizing block b by one-half and changes its 'characteristic. The apparatus controlled by amplifier A can be made selectively responsive to current of this characteristic, as in Fig. 3a. It will be noted that another train in block U ahead of train BI, 62, deenergizes the track circuit which usually leads to a stop effect.

The arrangement in Fig. '3 corresponds with Fig. 2 in the transformer arrangement except in the connection to the track rails for coils '44 and '49. The coil 44 connects to the rails II and 1:2

-,by wires 52a through .condenserx53a, :andythe coil 49 connects to the same rails by wires 5211 through condenser 531);- thus the current which energizes coil 49 from 44 must pass through the rail connections, thereby insuring the integrity of these connections. This construction is desirable where the shunt connections to the rail cannot be depended upon. The track circuit corresponds with that shown in Fig. 1.

The arrangement in Fig. 3a is modified from Fig. 1 to include three block control. The transformer core 42 has a secondary coil 15 connected by wires 16 and condenser 11 with the track rails. The circuit from this secondary is continued through wires 18 connecting to the track rails and condenser 19 to the coil of the transformer 8|. The secondary of this transformer 82 is connected by wires 35 and 36 with the full wave rectifier 31 which energizes transformer 84 by the coil 83, and by the secondary coil 85, wires 86, and condenser 81, feeds the track circuit. The character of the current used to feed the track circuit is modified by the rectifier 31 and also by coil 88, on the core 84, which connects by wires 89 with the track rails of the second block ahead. The current energizing coil 88 is subject to the reactions of the track circuit and is normally out of phase with the current energizing coil 83. Thus the current energizing coil 85, when the track is clear, is subject .to the superimposed currents in 83 and 88, and the train control apparatus is made selectively responsive to this current.

When blocks a and b, for instance, are clear a current of one characteristic is delivered to block 0 by coils 83 and 88 energized. When block a is occupied and block b is clear, a current of a different characteristic is delivered to block 0 by coil 83 only, and when block b is occupied and block a is occupied there is no effective current delivered to block 0, and when block b is occupied and block a is clear, the current energizing coil 88 is not suflicient of itself to energize the track circuit to produce proceed conditions on the vehicle. For instance when blocks a and b are clear, the current through amplifier A and the selector energizes 90 and SI. When a. is occupied and b is clear the energizing effect of coil 88 is absent and 9| is, in consequence, deenergized While 90 is energized, and when both a and b are occupied, 90 and 9! are deenergized.

The vehicle apparatus is provided with a selector responsive to the characteristics of the current-energizing the track circuit, and which selectively energizes the translating devices 98 and 9| to produce three position control.

In the arrangement described, frequency changes on the trackway were obtained by static apparatus. It is apparent, however, that a wider range of frequency to distinguish between the control circuit and the block circuit may be obtained by the use of separate transmission lines, .each energized with a different frequency range. J

It should be understood that the circuit is regarded as deenergized when the translating de vice-in the circuit has changed its position, or ceases to operate in the manner in which it operates when normally energized, although the circuit itself may not be deenergized in the sense The secondary of the second transformer is used to energize the trackWay YB circuit and a shunt is provided for the primary circuit of the second transformer by a vehicle on the track before its character is changed.

The first transformer is preferably of the open magnetic circuit type as indicated at 42, Fig. 2 to limit its output under shunting conditions.

Having thus described my invention, I claim:

1. In a block system, a railway track, a block circuit energized by current of one frequency, a controlling circuit energized by current of another frequency, means inductively coupling said circuits whereby said controlling circuit controls said block circuit, and a vehicle on said track arranged to shunt said controlling circuit as the vehicle moves along the track and having a translating device selectively responsive to said block circuit for controlling the movement of the vehicle on the track.

2. Ina block system, a railway track, a block circuit energized by current of one frequency, a controlling circuit energized by current of a lower frequency, means inductively coupling said circuits whereby said controlling circuit controls said block circuit, a vehicle on said track, means establishing electrical connection between said vehicle and said block circuit as the vehicle moves on the track, a translating device on said vehicle controlling the movement of the vehicle on the track and selectively energized by said block circuit and means on said vehicle for shunting said controlling circuit as it moves along the track independently of said block circuit.

3. A block system for controlling traflic on a railway track comprising a trackway circuit, a transformer for energiizng said circuit, a second transformer for energizing said first transformer, a car having means for shunting the secondary of said second transformer as it moves along the track, and a relay responsive to the current in the trackway circuit controlling traffic on the track.

4. A block system for controlling traflic on a railway track comprising a trackway circuit, a first transformer for energizing said circuit, a second transformer having a circuit for energizing said first transformer, means for changing the character of the current in said last named circuit for energizing the first transformer, a car having means for shunting the energy for said first transformer as it moves along the track, and a translating device responsive to the current in the trackway circuit for controlling traffic on the track.

5. A block system for controlling traific on a railway track comprising a trackway circuit, a first transformer for energizing said circuit, a second transformer having a secondary circuit with a rectifier therein for energizing said first transformer, a car having means for shunting the circuit of said second transformer as it moves along the track; before it is rectified and a translating device responsive to the current in the trackway circuit for controlling traflic on the track.

6. A blocksystem for controlling traffic on a railway track comprising a plurality of trackway circuits, a first transformer for energizing one of said trackway circuits, a second transformer having a secondary circuit with a rectifier therein for energizing said first transformer, a car on the track on another of said trackway circuits completing a shunt circuit including a condenser for the circuit of said second transformer before it is rectified and a translating device selectively responsive to the current in the first named trackway circuit controlling traffic on the track.

7. A block system for controlling trafiic on a railway track comprising a track divided into insulated sections, a first transformer for energizing one of said track sections, a second transformer having a secondary circuit for energizing said first transformer, a shunt circuit including a condenser for said secondary circuit connected to the rails of another of said sections for deenergizing the track circuit, and a translating device responsive to the current in the first named section for controlling trafiic on the track.

8. A block system for controlling traffic on a railway track comprising a first transformer for energizing a track circuit, a second transformer having a secondary circuit including a rectifier for energizing said first transformer, a shunt circuit for said secondary circuit connected to the rails of another portion of said track and connected to the shunt circuit between the rectifier and the second transformer for deenergizing the track circuit and a relay responsive to the energizing current of the track circuit for controlling traffic on the track.

9. A block system comprising a railway track divided into insulated sections, an A. C. transmission line, a first transformer having a primary connected to said transmission line, a second transformer connected to the secondary of the first transformer and also connected in shunt circuit through a condenser with the rails of one of the track sections, a full wave rectifier connected to the second transformer, a third transformer connected to the rectifier, the secondary of said third transformer connected to the rails of another track section and translating means selectively responsive to the current in the other track section from the third transformer controlling traflic on said track.

10. A block system comprising a railway track divided into insulated sections, a source of A. C. with a first transformer having a primary connected with said source, a second transformer connected to the secondary of the first transformer and also connected through a condenser in shunt with the rails of a track section, means inductively coupled with said second transformer for changing the character of the output current from this transformer, means connecting this output circuit to the rails of a track section to be shunted by a train as it moves along the track, and means selectively responsive to the current in said output circuit controlling trafilc on said track.

1 A block system for controlling traific comprising a railway track divided into insulated sections, a source of alternating current with a first transformer having a secondary circuit, connected with the track rails of one section, a second transformer having a primary energized from said secondary circuit, means for changing the frequency of the current between said first and second transformers, means connecting the secondary of the second transformer to the track rails of another section and means associated with the track selectively responsive to the current in the other track section.

12. A block system comprising a railway track divided into sections, a first transformer having a secondary coil feeding one track section, a primary coil on said transformer connected through a rectifier to a second transformer, a 7

third transformer connected with a source of alternating current and :having a secondary circuit energizing said second transformer, means connecting said secondary circuit in shunt with the rails of a second track section, another energizing coil on the first transformer connected with a third track section and means selectively responsive to the current in, the track circuit feed for controlling traific on the track.

13. A track feed for a block system comprising an insulated section of track, a source of alternating current, a transformer connected with said source and having a secondary circuit connected in shunt with the rails of said track section, a second transformer energized by said secondary circuit, a track feed circuit energized by the secondary of said second transformer and a translating device operatively connected with said track circuit and controlling traffic on the track.

14. In a block system, means for shunting a track circuit comprising a railway track divided into insulated sections or blocks, a transformer for energizing each section, a primary coil with a circuit for energizing said transformer, a shunt for said energizing circuit connected with an insulated rail section to be shunted by the train on this section and a relay responsive to the track circuit energy from the transformer controlling traffic on the track.

15. In a block system, means for shunting a track circuit comprising a railway track divided into insulated blocks, a transformer for energizing each block with a primary coil and a circuit for energizing said coil, a rectifier in said energizing circuit and a shunt for said energizing circuit before it is rectified connected with a block section to .be shunted by a train on this section and translating means responsive to the track circuit energy controlling traflic on the track.

16. A block system comprising a track divided into blocks with a trackway circuit for each block, means for energizing each track circuit with block current, a control circuit for each block circuit, means embodied in said control circuit producing a characteristic in said block circuit different from said control circuit, means for shunting said control circuit by a train as it moves along the track in one of said blocks and a translating device operatively associated with the trackway circuit selectively responsive to said block current and controlling traffic on the track.

MATTHEW I-I. LOUGHRIDGE. 

